meson: Add boost to the dependencies

Since the project uses boost library add it to meson dependencies.

Tested:
Local build no longer fails with a missing boost headers message on the
system without boost, but fails at the "meson setup build" stage with
an appropriate message.

Change-Id: I872159dcec923d289626b532146c9eb8d5461e1c
Signed-off-by: Konstantin Aladyshev <aladyshev22@gmail.com>
diff --git a/meson.build b/meson.build
index a2ea1e4..c48a930 100644
--- a/meson.build
+++ b/meson.build
@@ -64,6 +64,8 @@
 
 cpp = meson.get_compiler('cpp')
 
+boost_dep = dependency('boost')
+
 # Get Cereal dependency.
 cereal_dep = dependency('cereal', required: false)
 has_cereal = cpp.has_header_symbol(
@@ -89,6 +91,7 @@
 ]
 
 user_manager_deps = [
+     boost_dep,
      sdbusplus_dep,
      phosphor_logging_dep,
      phosphor_dbus_interfaces_dep
diff --git a/phosphor-ldap-config/meson.build b/phosphor-ldap-config/meson.build
index 925ff8d..24060ea 100644
--- a/phosphor-ldap-config/meson.build
+++ b/phosphor-ldap-config/meson.build
@@ -1,6 +1,7 @@
 ldap_dep = meson.get_compiler('cpp').find_library('ldap', required: true)
 
 phosphor_ldap_conf_deps = [
+    boost_dep,
     cereal_dep,
     phosphor_dbus_interfaces_dep,
     phosphor_logging_dep,